C++ File handling Program - c++

Question

Here I have tried to write a program write, update, display, delete, and print record. Display a menu of option and select an option to execute it.
Problem is that, "Neither default switch statement is executed nor 3 to 6 option executed."
Can someone point out the error/mistakes?
#include <iostream>
#include <fstream>
#include <windows.h>
#include <iomanip>
using namespace std;
void gotoxy(short x, short y) {
COORD pos = {x, y};
SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), pos);
}
struct data{
char mark;
char name[15],city[15];
};
class person{
public:
void addrec(void);
void update(void);
void disp_all(void);
void display(void);
void delrec(void);
void pack(void);
};
int main(){
person obj;
int ch;
while(1){
system("cls");
gotoxy(28,5);
cout<<"Person Records";
gotoxy(25,6);
cout<<"===================="; //20
gotoxy(25,7);
cout<<"1: Add Records ";
gotoxy(25,8);
cout<<"2: Update Records ";
gotoxy(25,9);
cout<<"3: Display All Records ";
gotoxy(25,10);
cout<<"4: Display Single Records ";
gotoxy(25,11);
cout<<"5: Mark Record for Deletion ";
gotoxy(25,12);
cout<<"6: Delete Records Permanently";
gotoxy(25,13);
cout<<"7: Exit ";
gotoxy(25,15);
cout<<"Enter Your choice [1-7] ";
cin>>ch;
switch(ch){
case 1: obj.addrec(); break;
case 2: obj.update(); break;
case 3: obj.disp_all(); break;
case 4: obj.display(); break;
case 5: obj.delrec(); break;
case 6: obj.pack(); break;
case 7: exit(1); break;
default:
cout<<"invalid choice ";
}
}
}
void person::addrec(void){
data rec;
char op;
ofstream add("employee.dat",ios::binary);
do{
system("cls");
cout<<"Enter Name of person: ";
cin>>rec.name;
cout<<"Enter City of person: ";
cin>>rec.city;
rec.mark=' ';
add.write((char*)&rec,sizeof(rec));
cout<<"More Records [Y/N]";
cin>>op;
}
while(op=='y'||op=='Y');
add.close();
}
void person::update(){
data rec;
char nm[15];
long int rn=0, t=0;
fstream update_Rec("employee.dat", ios::binary|ios::in|ios::out);
if(!update_Rec){
cerr<<"File opening error "<<endl;
exit(1);
}
cout<<"Enter Name of person ";
cin>>nm;
while(update_Rec.read((char*)&rec,sizeof(rec))){
if(strcmp(nm,rec.name)==0){
cout<<rec.mark<<rec.name<<"\t"<<rec.city<<endl;
rn=(rn)&sizeof(rec);
update_Rec.seekp(rn);
cout<<"Enter New name of person";
cin>>rec.name;
cout<<"Enter new city of Person";
cin>>rec.city;
update_Rec.write((char*)&rec,sizeof(rec));
update_Rec.close();
t=1;
}
rn++;
}
if(t==0)
cout<<"Record not found"<<endl;
}
void person::disp_all(void){
data rec;
char op;
ifstream disp_all_Rec("employee.dat",ios::binary);
if(!disp_all_Rec){
cerr<<"File opening error";
exit(1);
}
while(!disp_all_Rec.eof()){
disp_all_Rec.read((char*)&rec,sizeof(rec));
cout<<setw(15)<<bodyrec.mark<<rec.name<<setw(15)<<rec.city<<endl;
}
disp_all_Rec.close();
}
void person::display(void){
data rec;
char nm[15];
long int rn=0, t=0;
ifstream display_Rec("employee.dat",ios::binary);
if(!display_Rec){
cerr<<"File opening error";
exit(1);
}
cout<<"Enter name of person: ";
cin>>nm;
while(display_Rec.read((char*)&rec,sizeof(rec))){
if(strcmp(nm,rec.name)==0){
rn=(rn-1)*sizeof(rec);
display_Rec.seekg(rn);
cout<<rec.mark<<"\t"<<rec.name<<"\t"<<rec.city<<endl;
display_Rec.close();
t=1;
}
rn++;
}
if(t==0)
cout<<"Record not found"<<endl;
}
void person::delrec(){
data rec;
char nm[15];
long int rn=0,t=0;
fstream del("employee.dat",ios::in|ios::out);
if(!del){
cerr<<"File opening error"<<endl;
exit(1);
}
cout<<"Enter Name of person";
cin>>nm;
while(del.read((char*)&rec,sizeof(rec))){
if(strcmp(nm,rec.name)==0){
cout<<"Record is : "<<rec.mark<<"\t"<<rec.name<<"\t"<<rec.city<<endl;
if(rec.mark='*'){
cout<<"Record already Marked \n";
t=1;
}
else
{
rn=(rn)*sizeof(rec);
del.seekp(rn);
rec.mark='*';
del.write((char*)&rec,sizeof(rec));
cout<<"\n\n Record is marked for deletion \n";
del.close();
t=1;
}
rn++;
}
if(t==0)
cout<<"Record not found";
}
}
void person::pack(void){
data rec;
char nm[15];
long int rn=0;
ifstream pack_Rec("employee.dat",ios::binary);
ofstream pack_Rec_open("temp.dat",ios::binary);
if(!pack_Rec){
cerr<<"File opening error";
exit(1);
}
while(pack_Rec.read((char*)&rec,sizeof(rec))){
if(rec.mark!='*')
pack_Rec_open.write((char*)&rec,sizeof(rec));
rn++;
}
pack_Rec_open.close();
pack_Rec.close();
remove("employee.dat");
rename("temp.dat","employee.dat");
cout<<"Records are copies";
}
add records and update records are working properly but other functions are not properly?